Last night, i looked at adding a custom CSS file so that I can style my Views without having to change the Views.css file that is in the module itself.

My main concern is that the added CSS files (from the .info file) are still aggregated and cached for performance. And after checking a bit, I see that they are.

There are other considerations that need to be taken into account for CSS especially if you are doing specific things for IEx. Now that IE10 is out, maybe it will be better. But make sure to read up on this if you plan on making a lot of CSS changes.